System and method for digital communications using multiple parallel encoders

ABSTRACT

Devices and methods for processing wireless high definition video data to be communicated in an uncompressed format over a wireless medium is disclosed. In one embodiment, an encoder includes a first outer encoder that encodes a first portion of a video data stream. A second outer encoder encodes a second portion of the video data stream. A first parser parses the first encoded data stream into first sub-video data streams. A second parser parses the second encoded data stream into second sub-video data streams.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.11/724,758 filed on Mar. 15, 2007, which claims priority under 35 U.S.C.§119(e) from U.S. Provisional Patent Application No. 60/817,317 filed onJun. 28, 2006, which are herein incorporated by reference. U.S. Ser. No.11/724,758 is related to U.S. patent application Ser. No. 11/724,735 andU.S. patent application Ser. No. 11/724,760, which were concurrentlyfiled with U.S. patent application Ser. No. 11/724,758 and are alsoherein incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to wireless transmission of videoinformation, and in particular, to transmission of uncompressed highdefinition video information over wireless channels.

2. Description of the Related Technology

With the proliferation of high quality video, an increasing number ofelectronics devices (e.g., consumer electronics devices) utilizehigh-definition (HD) video, which has an overall data throughputrequirement on the order of multiple giga bps. In most wirelesscommunications, HD video is compressed first before transmitting to thewireless medium. Compression of the HD video is attractive because theoverall required communication bandwidth and power can be significantlyreduced, relative to transmission of the original, uncompressed video.However, with each compression and subsequent decompression of thevideo, some video information can be lost and the picture quality isdegraded. Furthermore, compression and decompression of the video signalincurs significant hardware cost as well.

The High-Definition Multimedia Interface (HDMI) specification defines aninterface for uncompressed HD transmission between devices through HDMIcables (wired links). Three separate channels are used to transmit threepixel component streams (e.g., R, B, G). For each channel, pixels aretransmitted in a pixel-by-pixel order for each video line andline-by-line for each video frame or field. The HDMI providespixel-repetition functionality which repeats each pixel one or multipletimes. Copies of each pixel directly follow the original pixel duringthe transmission at each pixel component channel.

It is also desirable to transmit uncompressed HD video over the area incertain scenario. However, existing wireless local area networks (WLANs)and similar technologies do not have the bandwidth needed to supportuncompressed HD video. Further, existing wireless networks may sufferfrom undesirable interference originated from nearby and neighboringusers, either of the same network or of other networks.

SUMMARY OF CERTAIN INVENTIVE ASPECTS

One aspect of the invention provides a system for processing highdefinition video data to be transmitted over a wireless medium, thesystem comprising: i) a Reed Solomon (RS) encoder configured to encode avideo data stream, and an outer-interleaver to reshuffle the coded bitsii) a parser configured to parse the RS encoded data stream into aplurality of sub-video data streams, iii) a plurality of convolutionalencoders configured to encode in parallel the plurality of sub-videodata streams so as to create a plurality of encoded data streams and iv)a multiplexer configured to input the plurality of encoded data streamsand output a multiplexed data stream, wherein the multiplexed datastream is transmitted over the wireless medium, received and decoded ata receiver.

Another aspect of the invention provides a method of processing highdefinition video data to be transmitted over a wireless medium, themethod comprising: i) Reed Solomon (RS) encoding a video data stream andinterleaving ii) parsing the RS encoded data stream into a plurality ofsub-video data streams, iii) convolutional encoding the plurality ofsub-video data streams in parallel so as to create a plurality ofencoded data streams and iv) multiplexing the plurality of encoded datastreams so as to output a multiplexed data stream, wherein themultiplexed data stream is transmitted over the wireless medium,received and decoded at a receiver.

Another aspect of the invention provides a system for processing highdefinition video data to be transmitted over a wireless medium, thesystem comprising: i) a first Reed Solomon (RS) encoder configured toinput the most (or more) significant bits (MSBs) of a video data stream,RS encode the MSBs, and output a first RS encoded data stream, followedby the first outer-interleaver which interleaves the first RS coded datastream ii) a second Reed Solomon (RS) encoder configured to input theleast (or less) significant bits (LSBs) of the video data stream, RSencode the LSBs, and output a second RS encoded data stream, followed bythe second outer-interleaver which interleaves the second RS coded datastream iii) a first parser configured to parse the first RS encoded datastream into a first plurality of sub-video data streams, iv) a secondparser configured to parse the second RS encoded data stream into asecond plurality of sub-video data streams, v) a first plurality ofconvolutional encoders configured to encode the first plurality ofsub-video data streams in parallel and output a first plurality ofconvolutional encoded data streams, vi) a second plurality ofconvolutional encoders configured to encode the second plurality ofsub-video data streams in parallel and output a second plurality ofconvolutional encoded data streams, vii) a multiplexer configured toinput the first and the second plurality of convolutional encoded datastreams and output an overall multiplexed data stream, which is thenmodulated and transmitted over the wireless medium, received and decodedat a receiver.

Still another aspect of the invention provides one or moreprocessor-readable storage devices having processor-readable codeembodied on the processor-readable storage devices, theprocessor-readable code for programming one or more processors toperform a method of processing high definition video data to betransmitted over a wireless medium, the method comprising: i) ReedSolomon (RS) encoding a video data stream, ii) parsing the RS encodeddata stream into a plurality of sub-video data streams, iii)convolutional encoding the plurality of sub-video data streams inparallel so as to create a plurality of encoded data streams and iv)multiplexing the plurality of encoded data streams so as to output amultiplexed data stream, wherein the multiplexed data stream istransmitted over the wireless medium, received and decoded at areceiver.

Yet another aspect of the invention provides a system for processinghigh definition video data to be transmitted over a wireless medium, thesystem comprising: i) an outer encoder configured to encode a video datastream and an outer interleaver to interleave the encoded stream, ii) aparser configured to parse the encoded data stream into a plurality ofsub-video data streams, iii) a plurality of inner encoders configured toencode the plurality of sub-video data streams in parallel so as tocreate a plurality of encoded data streams and iv) a multiplexerconfigured to input the plurality of encoded data streams and output amultiplexed data stream.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a functional block diagram of a wireless network thatimplements uncompressed HD video transmission between wireless devicesaccording to one embodiment.

FIG. 2 is a functional block diagram of an example communication systemfor transmission of uncompressed HD video over a wireless medium,according to one embodiment.

FIG. 3 illustrates an exemplary wireless HD video transmitter systemaccording to one embodiment of the invention.

FIG. 4 illustrates an exemplary wireless HD video transmitter systemaccording to another embodiment of the invention.

FIG. 5 illustrates an outer interleaver at a transmitter site and anouter deinterleaver at a receiver site according to one embodiment ofthe invention.

FIG. 6 illustrates an exemplary flowchart which shows a wireless HDvideo transmitting procedure according to one embodiment of theinvention.

DETAILED DESCRIPTION OF CERTAIN INVENTIVE EMBODIMENTS

Certain embodiments provide a method and system for transmission ofuncompressed

HD video information from a sender to a receiver over wireless channels.

Example implementations of the embodiments in a wireless high definition(HD) audio/video (A/V) system will now be described.

FIG. 1 shows a functional block diagram of a wireless network 100 thatimplements uncompressed HD video transmission between A/V devices suchas an A/V device coordinator and A/V stations, according to certainembodiments. In other embodiments, one or more of the devices can be acomputer, such as a personal computer (PC). The network 100 includes adevice coordinator 112 and multiple A/V stations 114 (e.g., Device 1 . .. Device N). The A/V stations 114 utilize a low-rate (LR) wirelesschannel 116 (dashed lines in FIG. 1), and may use a high-rate (HR)channel 118 (heavy solid lines in FIG. 1), for communication between anyof the devices. The device coordinator 112 uses a low-rate channel 116and a high-rate wireless channel 118, for communication with thestations 114.

Each station 114 uses the low-rate channel 116 for communications withother stations 114. The high-rate channel 118 supports single directionunicast transmission over directional beams established by beamforming,with e.g., multi-GB/s bandwidth, to support uncompressed HD videotransmission. For example, a set-top box can transmit uncompressed videoto a HD television (HDTV) over the high-rate channel 118. The low-ratechannel 116 can support bi-directional transmission, e.g., with up to 40Mbps throughput in certain embodiments. The low-rate channel 116 ismainly used to transmit control frames such as acknowledgement (ACK)frames. For example, the low-rate channel 116 can transmit anacknowledgement from the HDTV to the set-top box. It is also possiblethat some low-rate data like audio and compressed video can betransmitted on the low-rate channel between two devices directly. Timedivision duplexing (TDD) is applied to the high-rate and low-ratechannel. At any one time, the low-rate and high-rate channels cannot beused in parallel for transmission, in certain embodiments. Beamformingtechnology can be used in both low-rate and high-rate channels. Thelow-rate channels can also support omni-directional transmissions.

In one example, the device coordinator 112 is a receiver of videoinformation (hereinafter “receiver 112”), and the station 114 is asender of the video information (hereinafter “sender 114”). For example,the receiver 112 can be a sink of video and/or audio data implemented,such as, in an HDTV set in a home wireless network environment which isa type of WLAN. In another embodiment, the receiver 112 may be aprojector. The sender 114 can be a source of uncompressed video oraudio. Examples of the sender 114 include a set-top box, a DVD player orrecorder, digital camera, camcorder, other computing device (e.g.,laptop, desktop, PDA, etc.), and so forth.

FIG. 2 illustrates a functional block diagram of an examplecommunication system 200. The system 200 includes a wireless transmitter202 and wireless receiver 204. The transmitter 202 includes a physical(PHY) layer 206, a media access control (MAC) layer 208 and anapplication layer 210. Similarly, the receiver 204 includes a PHY layer214, a MAC layer 216, and an application layer 218. The PHY layersprovide wireless communication between the transmitter 202 and thereceiver 204 via one or more antennas through a wireless medium 201.

The application layer 210 of the transmitter 202 includes an A/Vpre-processing module 211 and an audio video control (AV/C) module 212.The A/V pre-processing module 211 can perform pre-processing of theaudio/video such as partitioning of uncompressed video. The AV/C module212 provides a standard way to exchange A/V capability information.Before a connection begins, the AV/C module negotiates the A/V formatsto be used, and when the need for the connection is completed, AV/Ccommands are used to stop the connection.

In the transmitter 202, the PHY layer 206 includes a low-rate (LR)channel 203 and a high rate (HR) channel 205 that are used tocommunicate with the MAC layer 208 and with a radio frequency (RF)module 207. In certain embodiments, the MAC layer 208 can include apacketization module (not shown). The PHY/MAC layers of the transmitter202 add PHY and MAC headers to packets and transmit the packets to thereceiver 204 over the wireless channel 201.

In the wireless receiver 204, the PHY/MAC layers 214, 216 process thereceived packets. The PHY layer 214 includes a RF module 213 connectedto the one or more antennas. A LR channel 215 and a HR channel 217 areused to communicate with the MAC layer 216 and with the RF module 213.The application layer 218 of the receiver 204 includes an A/Vpost-processing module 219 and an AV/C module 220. The module 219 canperform an inverse processing method of the module 211 to regenerate theuncompressed video, for example. The AV/C module 220 operates in acomplementary way with the AV/C module 212 of the transmitter 202.

Error control coding is widely used in modern communication systems. Forexample, a Reed Solomon (RS) code concatenated with a convolutional codehas been employed in protecting data against channel errors in manysystems, such as “Digital Video Broadcasting; framing structure, channelcoding and modulation for digital terrestrial television,” ETSI EN 300744, which is incorporated herein by reference. In typical communicationapplications, the data throughput is not very high, and at the receiverside, one RS decoder concatenated with one Viterbi algorithm (populardecoding algorithm for the convolutional code) is generally able tohandle the decoding task. However, this is not the case for wireless HD(WiHD) technology, where the targeted data throughput is on the order ofabout 4 Giga bits per second. In one embodiment, considering the factthat current Viterbi throughput is typically on the order of about 500Mega bits per second, multiple parallel Viterbi decoders are used at thereceiver to complete the decoding task. In this situation, when a singleencoder is used at a WiHD video transmitter, each of the multipledecoders needs to communicate data with each other because theinformation of one decoder is interrelated to the information of theremaining decoders. This makes the decoder design more complicated.Furthermore, communicating with other decoders can cause large overalldecoding delay at a WiHD receiver.

FIG. 3 illustrates an exemplary wireless HD video transmitter system 300according to one embodiment of the invention. The system 300 includes RSencoders 310 and 330, outer interleavers 312 and 332, parsers 314 and334, a first plurality of convolutional encoders 316-322 and a secondplurality of convolutional encoders 336-342, multiplexers 324 and 344and interleaving/mapping units 326 and 346. In one embodiment, all ofthe elements of the FIG. 3 system belong to the PHY layer 206 (see FIG.2). Although eight encoders are illustrated in FIG. 3, there may be moreencoders (e.g., 16 or greater) or less encoders (e.g., 2 or 4) dependingon specific applications. In another embodiment, it is also possible tohave a single RS encoder, a single outer interleaver, a single parserand a single multiplexer. In this embodiment, the single parser, insteadof having one input and four outputs as each of the parsers 314/334does, will have one input and eight outputs. In another embodiment,other encoder (or outer encoder), for example, a BCH code, may be usedfor encoding instead of the RS encoders 310 and 330.

In one embodiment, the elements 310-326 are used to process mostsignificant bits (MSBs) and the elements 330-346 are used to processleast significant bits (LSBs). It is known that for color reproductionthe loss of LSBs in a communication channel is of less concern than lossof MSBs. Therefore, certain embodiments can provide a greater degree ofprotection through, e.g., different error codings for each of MSBs andLSBs. This technique is known as unequal error protection (UEP). In oneembodiment, all of the elements of the FIG. 3 system can be embodied byeither software or hardware or a combination.

The RS encoders 310, 330 and outer interleavers 312, 332 perform RSencoding and interleaving on incoming bit streams (MSBs and LSBs,respectively). The parsers 314, 334 parse the interleaved bit streamsinto the first group of convolutional encoders 316-322 (for MSBs) andinto the second group of convolutional encoders 336-342 (for LSBs),respectively. In one embodiment, the parsers 314, 334 are a switch ordemultiplexer which parses data bit-by-bit or group-by-group (with thegroup size, number of bits in a group being not fixed). In oneembodiment, each of the outer interleavers 312, 332 is a blockinterleaver, a convolutional interleaver or an arbitrary interleaverwhich shuffles the order of the input data streams. In anotherembodiment, other forms of interleavers are also possible. In oneembodiment, the RS encoders 310, 330, outer interleavers 312, 332 andthe encoders 316-322 and 336-342 together perform the forward errorcorrection (FEC) described with respect to FIG. 2.

In one embodiment, the convolutional (or inner) encoders 316-322 and336-342 are configured to provide unequal error protection (UEP)depending on the relative importance of incoming data bits. As discussedabove, the first encoders 316-336 may encode MSB data and the secondencoders 336-342 may encode LSB data. In this example, the MSB encodingprovides better error protection than the LSB encoding. In anotherembodiment, the convolutional encoders 316-342 are configured to provideequal error protection (EEP) for all incoming data bits. Themultiplexers 324, 344 combine the bit streams of the encoders 316-322and 336-342, respectively. The interleaving/mapping units 326, 346perform interleaving/mapping on the outputs of the multiplexers 324,344, respectively. After the interleaving/mapping, the OFDM modulation,e.g., including inverse Fourier Fast Transform (IFFT) processing, andbeamforming may be performed before transmitting the data packet to aWiHD video data receiver over the wireless channel 201 (see FIG. 2). Inone embodiment, the WiHD video data receiver may include a plurality ofparallel convolutional decoders corresponding to the plurality ofconvolutional encoders 316-322 and 336-342.

FIG. 4 illustrates an exemplary wireless HD video transmitter system 400according to another embodiment of the invention. The system 400includes an RS encoder 410, an outer interleaver 420, a parser 430, aplurality of convolutional encoders 440-454, a multiplexer 460 and aninterleaving/mapping unit 470. In one embodiment, all of the elements ofthe FIG. 4 system belong to the PHY layer 206 (see FIG. 2). Althougheight encoders are illustrated in FIG. 3, there may be more encoders(e.g., 16 or greater) or less encoders (e.g., 2 or 4) depending onspecific applications. In one embodiment, the RS encoder 410, the outerinterleaver 420, the parser 430, the multiplexer 460 and theinterleaving/mapping unit 470 are substantially the same as those ofFIG. 3. In one embodiment, the encoders 440-454 are configured toprovide equal error protection (EEP) for all incoming data bits.

Hereinafter, referring to FIG. 6, the operation of the systems 300 and400 will be described. FIG. 5 will be discussed below. FIG. 6illustrates an exemplary flowchart which shows a wireless HD videotransmitting procedure 600 according to one embodiment of the invention.In one embodiment, the transmitting procedure 600 is implemented in aconventional programming language, such as C or C++ or another suitableprogramming language. In one embodiment of the invention, the program isstored on a computer accessible storage medium at a WiHD transmitterwhich is a part of or attached to a station, for example, a devicecoordinator 112 or devices (1-N) 114 as shown in FIG. 1. In anotherembodiment, the program can be stored in other system locations so longas it can perform the transmitting procedure 600 according toembodiments of the invention. The storage medium may comprise any of avariety of technologies for storing information. In one embodiment, thestorage medium comprises a random access memory (RAM), hard disks,floppy disks, digital video devices, compact discs, video discs, and/orother optical storage mediums, etc.

In another embodiment, at least one of the device coordinator 112 anddevices (1-N) 114 comprises a processor (not shown) configured to orprogrammed to perform the transmitting procedure 600. The program may bestored in the processor or a memory of the coordinator 112 and/or thedevices (1-N) 114. In various embodiments, the processor may have aconfiguration based on Intel Corporation's family of microprocessors,such as the Pentium family and Microsoft Corporation's Windows operatingsystems such as Windows 95, Windows 98, Windows 2000 or Windows NT. Inone embodiment, the processor is implemented with a variety of computerplatforms using a single chip or multichip microprocessors, digitalsignal processors, embedded microprocessors, microcontrollers, etc. Inanother embodiment, the processor is implemented with a wide range ofoperating systems such as Unix, Linux, Microsoft DOS, Microsoft Windows2000/9x/ME/XP, Macintosh OS, OS/2 and the like. In another embodiment,the transmitting procedure 600 can be implemented with an embeddedsoftware. Depending on the embodiments, additional states may be added,others removed, or the order of the states changes in FIG. 6.

In state 610, RS encoding is performed on the incoming data streams. Inone embodiment, on each stream, raw bits are first encoded by the RSencoders 310, 330 as shown in the system of FIG. 3. In anotherembodiment, a single RS encoder 410 is used to encode the entire rawdata information without splitting it into two separate streams, asillustrated in the system of FIG. 4.

In one embodiment, an RS code (n; 224, k; 220, t; 2) is used to RSencode the received data streams, where information data length k=220bytes, coded data length n=224 bytes and error correction capability t=2bytes. Equations (1)-(4) below show exemplary polynomials for RSencoding. In one embodiment, the RS code (224, 220, 2) is obtained byshortening an RS code (255, 251, 2), which has symbols in the Galoisfield GF (256), with the primitive polynomial being.

p(x)=1+x ² +x ³ +x ⁴ +x ⁸.  (1)

The codeword generator polynomial is chosen as

g2(x)=x ⁴+α⁷⁶ x ³+α²⁵¹ x ²+α⁸¹+α¹⁰.  (2)

In one embodiment, the shortened RS code can be implemented by adding 31bytes of zeros before the length-220 raw data bytes at the input of anRS encoder having an RS code (255, 251, 2). After the RS encodingprocedure, the 31 null bytes are discarded. In one embodiment, the sameRS encoder is used on both data streams (i.e., MSBs and LSBs)

In another embodiment, instead of the above RS code (224, 220, 2), an RScode (n; 224, k; 218, t; 3) can be used, where information data lengthk=218 bytes, coded data length n=224 bytes and error correctioncapability t=3 bytes. In another embodiment, an RS code (n; 224, k; 216,t; 4) can be also used. In one embodiment, the RS code (224, 218, 3) isobtained by shortening an RS code (255, 251, 3), which has symbols inthe Galois field GF (256), with the primitive polynomial being

p(x)=1+x ² +x ³ +x ⁴ +x ⁸.  (3)

The generator polynomial is chosen as

g3(x)=x ⁶+α¹⁶⁷ x ⁵+α¹²² x ⁴+α¹³⁴ x ³+α³⁴ x ²+α¹⁸¹ x+α ²¹.  (4)

In one embodiment, the shortened RS code can be implemented by adding 31bytes of zeros before the length-218 raw data bytes at the input of anRS encoder having an RS code (255, 249, 3). After the RS encodingprocedure, the 31 null bytes are discarded. Again, the same RS code maybe used for both streams of MSBs and LSBs. It is appreciated that theabove-described RS codes are merely examples, and other RS codes can beused.

Outer interleaving is performed on the output of the RS encoders (620).In one embodiment as shown in FIG. 3, the same outer interleaver is usedon both data streams (MSBs, LSBs). In another embodiment, the outerinterleavers on the two branches can be different. In one embodiment, anouter interleaver 510 (at a WiHD video transmitter) and a correspondingdeinterleaver 520 (at a WiHD video receiver) as shown in FIG. 5 areused. In another embodiment, interleavers and correspondingdeinterleavers having different configuration can also be used. In oneembodiment, the convolutional outer interleaver is described in G.Formey, “Burst Correcting Codes for Classic Bursty Channel,” IEEE Trans.on Communications Technology, vol. 19, no. 5, October 1971, which isincorporated by reference. In this embodiment, the interleaver iscomposed of I=8 branches, cyclically connected to the inputbyte-streams. In one embodiment, each branch is a first-in first-out(FIFO) shift register with delay jD, where D=28 is the delay per delayunit and j is the branch index. The cells of the FIFO may contain 1byte. The parameters I=8, D=28 are only an example. Other parameters canbe used depending on different situations. Also, here, the outerinterleaver is not necessarily a convolutional interleaver, and it canbe an arbitrary interleaver with arbitrary interleaving pattern.

The outer interleaved bit streams are parsed into multiple parallelconvolutional encoders (630). In one embodiment, the output is parsedinto N branches, with each branch encoded by a separate convolutionalencoder. In one embodiment, N=4 (2N=8) is used for the system of FIG. 3.In another embodiment, N=8 is used for the system of FIG. 4. In oneembodiment, the parser 508 parses the received pixels in a bit-by-bit orgroup-by-group manner. The group size depends on the input video formatand/or specific applications. In one embodiment, the input video formatis pixel by pixel. In another embodiment, the input video data isretrieved from, e.g., three memories which include data for one color,e.g., red, green and blue, respectively. A detailed descriptionregarding the operation of a group parser is explained in U.S. patentapplication Ser. No. 11/724,735 entitled “System and method for digitalcommunications having parsing scheme with parallel convolutionalencoders” concurrently filed as this application, which is incorporatedby reference.

Parallel encoding is performed on the parsed bit streams (640). Typicalvideo pixels have three colors R, G and B, with each color of a pixelcarrying 8 bits of information, resulting into 24 bits per pixel intotal. In one embodiment, each bit of the data is equally protected(EEP). In another embodiment, each bit of the data is unequallyprotected (UEP).

In one embodiment, as shown in FIG. 3, raw data information is firstsplit into two data streams, with bits 7, 6, 5, 4 going to the firststream (see the elements 310-326) and bits 3, 2, 1, 0 going to thesecond stream (see the elements 330-346). For 8 bits per color perpixel, bits 7, 6, 5, 4 are normally classified as MSBs and bits 3, 2, 1,0 are normally classified as LSBs. In one embodiment, there is nopriority difference between colors R, G and B.

In another embodiment, as shown in FIG. 4, raw data information isdirectly split into eight branches, with each bit going to one branch.In one embodiment, there is no priority difference between colors R, Gand B. In the UEP case, most significant bits (MSBs) are to be morestrongly protected than least significant bits (LSBs). These two datastreams are unequally protected via choice of different convolutionalcodes or puncturing patterns. In this embodiment, one code is adopted bythe N branches of the first stream (MSBs; 7, 6, 5, 4), and the othercode is adopted by the N branches of the second stream (LSBs; 3, 2, 1,0). In one embodiment, the two different codes can be generated from thesame mother code, through different puncturing patterns. Or, the twodifferent codes can be generated from different mother codes. In the EEPcase, most significant bits (MSBs) are to be as strongly protected asleast significant bits (LSBs). These two data streams are equallyprotected via the choice of same convolutional codes or puncturingpatterns. In another embodiment, more important bits (can include MSBsbut are not necessarily limited to MSBs) can be more strongly protectedthan less important bits (can include LSBs but are not necessarilylimited to LSBs).

After convolutional encoding over each branch, the coded data bits aremultiplexed together (650). In one embodiment, the outputs of the 2N(=8) convolutional encoders as shown in FIG. 3 are then multiplexedtogether and fed into the interleaving/mapping units 326, 346. Inanother embodiment, the output of the N (=8) convolutional encoders asshown in FIG. 4 are multiplexed together and provided to theinterleaving/mapping unit 470. The detailed multiplexing operation canbe found in U.S. patent application U.S. patent application Ser. No.11/724,760 entitled “System and method for digital communications havingpuncture cycle based multiplexing scheme with unequal error protection(UEP),” concurrently filed as this application, which is incorporated byreference.

One embodiment of the invention provides strong error protection fordata communications at very high throughput, and makes parallel Viterbidecoding implementation easier at a WiHD receiver. For example, becausethe decoders do not need to communicate data with each other whiledecoding, large decoding delay can be significantly reduced at thereceiver side. Furthermore, it supports both equal error protection andunequal error protection capability for video transmissions.

While the above description has pointed out novel features of theinvention as applied to various embodiments, the skilled person willunderstand that various omissions, substitutions, and changes in theform and details of the device or process illustrated may be madewithout departing from the scope of the invention. For example, althoughembodiments of the invention have been described with reference touncompressed video data, those embodiments can be applied to compressedvideo data as well. Furthermore, instead of a convolutional encoder,other inner encoder (e.g., linear block encoder) may be used. Therefore,the scope of the invention is defined by the appended claims rather thanby the foregoing description. All variations coming within the meaningand range of equivalency of the claims are embraced within their scope.

1. A method for receiving a high definition video data stream over awireless medium, the method comprising: receiving and decoding amultiplexed data stream encoded by a process including: encoding a firstportion of a video data stream by a first encoder; encoding a secondportion of the video data stream by a second encoder; parsing theencoded first portion of the data stream by a first parser into a firstplurality of sub-video data streams; parsing the encoded second portionof the data stream by a second parser into a second plurality ofsub-video data streams; and convolutional encoding the first and secondplurality of sub-video data streams in parallel so as to create aplurality of encoded data streams by a first and second plurality ofconvolutional encoders; and inputting the plurality of encoded datastreams and outputting a multiplexed data stream.
 2. The method of claim1, wherein the convolutional encoding comprising encoding the mostsignificant bits with an encoding rate different from that for the leastsignificant bits.
 3. The method of claim 1, wherein the first encoderand the second encoder are Reed Solomon (RS) encoders.
 4. The method ofclaim 1, wherein the convolutional encoding provides unequal errorprotection for incoming data bits depending on their relativeimportance.
 5. The method of claim 1, wherein the convolutional encodingcomprising encoding the most significant bits with an encoding ratedifferent from that for the least significant bits.
 6. The method ofclaim 1, wherein the multiplexed data stream is uncompressed.
 7. Themethod of claim 1, wherein the multiplexed data stream is received overthe wireless medium, and decoded at a receiver.
 8. A transmitter fortransmitting high definition video data in an uncompressed format over awireless medium, the transmitter comprising: a first encoder thatencodes a first portion of a video data stream; a second encoder thatencodes a second portion of the video data stream; a first parser thatparses the first encoded data stream into a first plurality of sub-videodata streams; a second parser that parses the second encoded data streaminto a second plurality of sub-video data streams; and a convolutionalencoding module for convolutional encoding the first plurality ofsub-video data streams and the second plurality of sub-video datastreams; and a multiplexer that inputs the first and second plurality ofconvolutional encoded data streams and outputs a single multiplexed datastream for transmitting over the wireless medium.
 9. The transmitter ofclaim 8, wherein the convolutional module comprises: a first pluralityof convolutional encoders that encode the first plurality of sub-videodata streams in parallel and output a first plurality of convolutionalencoded data streams; and a second plurality of convolutional encodersthat encode the second plurality of sub-video data streams in paralleland output a second plurality of convolutional encoded data streams. 10.The transmitter of claim 8, wherein the first encoder comprises a firstReed Solomon (RS) encoder and the second encoder comprises a second RSencoder.
 11. The transmitter of claim 10, wherein the first RS encoderinputs the most significant bits (MSBs) of the video data stream, RSencodes the MSBs, and outputs a first RS encoded data stream; and thesecond RS encoder inputs the least significant bits (LSBs) of the videodata stream, RS encodes the LSBs, and outputs a second RS encoded datastream.
 12. The transmitter of claim 11, further comprising: a firstouter interleaver that performs interleaving on the output of the firstRS encoder and provides the interleaved data to the first parser; and asecond outer interleaver that performs interleaving on the output of thesecond RS encoder and provide the interleaved data to the second parser.13. The transmitter of claim 12 wherein each of the first and secondouter interleavers includes I branches, cyclically connected to inputbyte-streams, and wherein each branch is a first-in first-out (FIFO)shift register with delay jD, where D is delay per a delay unit and j isa branch index.
 14. An encoder for processing high definition video datato be transmitted over a wireless medium, the encoder comprising: afirst outer encoder that encodes a first portion of a video data stream;a second outer encoder that encodes a second portion of the video datastream; a first parser that parses the first encoded data stream into afirst plurality of sub-video data streams; and a second parser thatparses the second encoded data stream into a second plurality ofsub-video data streams.
 15. The encoder of claim 14, further comprising:a plurality of inner encoders that encode the first and second pluralityof sub-video data streams in parallel for creating a plurality ofencoded data streams; and a multiplexer that inputs the plurality ofencoded data streams and outputs a multiplexed data stream.
 16. Theencoder of claim 15, wherein the outer encoder is a Reed Solomon encoderor a Bose-Chaudhuri-Hochquenghem (BCH) encoder.
 17. The encoder of claim16, wherein each of the inner encoders is a convolutional encoder or alinear block encoder.
 18. A wireless receiver for receiving highdefinition video data transmitted over a wireless medium, the receivercomprising: an RF unit that receives encoded data streams over thewireless medium; and a plurality of parallel convolutional decoders fordecoding a data stream encoded by a first Reed Solomon (RS) encoder thatencoded a first portion of the video data stream, and a second RSencoder that encoded a second portion of the video data stream.
 19. Thewireless receiver of claim 18, wherein the decoded data stream comprisesan encoded data stream encoded by a first and second plurality ofconvolutional encoders that encode a first and second plurality ofsub-video data streams in parallel.
 20. The wireless receiver of claim19, wherein the receiver is a HDTV set or a projector.
 21. The wirelessreceiver of claim 20, wherein the wireless receiver is implemented withone of the following: a set-top box, a DVD player or recorder, a digitalcamera, a camcorder and other computing device.
 22. The wirelessreceiver of claim 19, wherein the number of the first and secondplurality of convolutional encoders is 8, wherein the first fourconvolutional encoders encode four most significant bits of the firstplurality of sub-video data streams and the remaining four convolutionalencoders encode four least significant bits of the second plurality ofsub-video data streams, and wherein the first four and the remainingfour convolutional encoders use different convolutional codes.